In the art of manufacturing molded plastic containers and the like, blow molding processes and injection molding processes have evolved. Relatively thin walled containers of a high density polyethylene (HDPE) polymer material can be blow molded using certain polymers and certain blow molding equipment. For example, HDPE polymers for blow molding consumer milk containers have a density of approximately 0.960 to 0.965 g/cc. On the other hand, relatively low to medium density polyethylene polymers (0.900 to 0.960 g/cc) are used in thicker walled, non-rigid containers such as large trashcans. HDPE grade resins for blow molding typically have a melt index of about 0.7 to 1.0 grams/10 min., whereas resins and polymers for injection molding have a melt index of about 6.0 or more grams/10 min.
In manufacturing containers for agricultural applications such as livestock feed tubs and the like, it is desirable to provide a rigid, durable container which is economical to produce and uses a minimum amount of polymer material. Those manufacturers equipped with injection molding equipment for manufacturing components/containers would benefit from being able to use a blow molding grade HDPE resin, but the expense of adding blow molding equipment to the manufacturing assets may not be warranted. Moreover, until now, the ability to use injection molding equipment to mold parts with a blow molding grade resin has not been successful, principally in part because of the low melt index and slow flow characteristics of blow molding resins. It is to these ends that the present invention has been developed.